Paul C. Buff, Inc. Technical Forum

We shoot portraits and interiors with the X800's and frequently reduce power. Do they produce consistent color temperature from shot to shot. We use a wibal grey card in the first shot in each series, but then shoot 50 or so shots and find that the color balance (temperature) seems to vary from shot to shot.
We then take the RAW file in bridge and color balance the first, and syncronize all photos.
It is difficult to include a wibal card in each and every shot. Would a McBeth color chart work better?
We've also tried expo disc with mixed results. We balance for the first and syncronize.
Finally, would it be better to sell the x800's and switch to Einsteins, which are supposed to have consistent color temperature thoroughour the power range?

Brad Jaeck
Photographic Design

Generally speaking, yes. If not, there may be an issue with a specific head.

After the Whi Bal reference shot, do you change power, location, modifiers, or other camera settings?

Are your exposures varying?

How fast are you firing? If you fire too fast, you may be catching the light at different points in the recycle phase.

Since the units are low, are you mixing ambient light? If so, what kind of light, and what are your typical shutter speeds?

With the portraits we typically shoot at 1/50 th second. No ambient light, For the interiors it's 1/2 second to bring in some ambient light.

The portraits are done in a rather dark studio and we use only strobe, typically at 1/4 power.
The interior shots are done at 1 second to 1/10th. exposures so the outdoors comes in.

However it still seems like each exposure is slightly different, and nothing changes.

Brad

Is it just color, or also exposure?

Are you shooting RAW?


After you sample the first photo and sync the others, can you go from one image to the next and see the color temperature and tint settings are the same?

A Macbeth color chart would probably exhibit the same problems, if you used the same procedures otherwise. Using something akin to this to set up a complete color profile may or may not help.

We are shooting RAW always. When shooting portraits the shadows and some highlights appear to be missing some of the color gamit. That's why I was asking if reducing the power cuts anything out of the spectrum and if the Einstein's might work better. They all seem to be the same and using the whibal in the raw mode seems to correct color doesn't help. We always seem to have to go in and do more color correcting even with the white balance card and balancing in RAW. I had a similiar situation years ago in florescent light whereby it was missing some of the spectrum.
It shouldn't be that difficult to get good flesh tones....every time.
Brad

There should not be a significant color shift without a significant exposure shift. There may be some impact from ambient light, even if it does not appear in non flash exposures. The variations could be from the ambient. To verify, a test with each light should be performed. Photos should be taken at higher shutter speeds to reduce ambient contributions. 1/160 to 1/250 would be better. A series of photos should be taken and processed in the same manner as the regular shots.